I have no problem with his looks. I never expect a 100% cross-over look when comic goes to film. What I look for is the spirit of the character. For example, I feel the Toby M. as Spiderman worked out perfectly. He had the teenager aspects, the "nothing goes right for the hero" drama, and you notice, he just seemed to be Parker. On the other hand, I felt that Micheal Keaton as Batman failed. He just wasn't "dark" enough, foreboding, mentally strengthened.

As Iron Man, Downey has to fill a psychological suit. I'm sure he is aware of this...all actors should be. If he takes it serious, and the Director molds it well to the screen, should be great.

On the other hand, Iron Man, at least the first movie, should be on a magnanimous level...about the suit. Tony Stark's heart attack and story line (IMHO) shouldn't take more than 20 minutes. IF THIS OCCURS, you will be able to see the awesome power of the Iron Man. If you pull a move like Ang Lee in the Incredible Hulk, then you'll have nearly 45 minutes of...story...when all people really want is the huge green monster. (Just a note: I really appreciated how fast Rami implemented Spiderman's origin in the movie)

In summary, I am sure Downey can do the part. It's a little too early to give a thumbs up or down.